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co2 Lasers in High Energy Physics.

Description: Several proof-of-principle laser accelerator experiments turned a long-wavelength of a CO{sub 2} laser to advantage. Ongoing advancement to multi-terawatt femtosecond CO{sub 2} lasers opens new venues for next-generation laser acceleration research.
Date: December 3, 2001
Creator: Pogorelsky, I. V.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Counter Propagation of Electron and CO2 Laser Beams in a Plasma Channel

Description: A high-energy CO{sub 2} laser is channeled in a capillary discharge. Occurrence of guiding conditions at a relatively low plasma density (<10{sup 18} cm{sup -3}) is confirmed by MHD simulations. Divergence of relativistic electron beam changes depending on the plasma density. Counter-propagation of the electron and laser beams inside the plasma channel results in intense x-ray generation.
Date: November 12, 2002
Creator: Hirose, T.; Pogorelsky, I. V.; Ben-Zvi, Ilan; Yakimenko, V.; Kusche, K.; Siddons, P. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Tritium Removal by CO{sub 2} Laser Heating

Description: Efficient techniques for rapid tritium removal will be necessary for ITER (International Thermonuclear Experimental Reactor) to meet its physics and engineering goals. One potential technique is transient surface heating by a scanning CO(subscript 2) or Nd:Yag laser that would release tritium without the severe engineering difficulties of bulk heating of the vessel. We have modeled the heat propagation into a surface layer and find that a multi-kW/cm(superscript2) flux with an exposure time of … more
Date: October 1, 1997
Creator: Doyle, B. L.; Skinner, C. H.; Mueller, D.; Kugel, H. & Wampler, W. R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Primary Tests of Laser/E Beam Interaction in a Plasma Channel

Description: A high-energy CO{sub 2} laser is channeled in a capillary discharge. Plasma dynamic simulations confirm occurrence of guiding conditions at the relatively low axial plasma density 1 {divided_by} 4 x 10{sup 17} cm{sup -3}. A relativistic electron beam transmitted through the capillary changes its properties depending upon the plasma density. We observe focusing, defocusing or steering of the e-beam. Counter-propagation of the electron and laser beams in the plasma channel results in generation o… more
Date: June 23, 2002
Creator: Pogorelsky, I. V.; Ben-Zvi, Ilan; Hirose, T.; Yakimenko, V.; Kusche, K.; Siddons, P. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Gas breakdown limits for inverse Cherenkov laser accelerators

Description: The probability of avalanche, tunneling and multiphoton ionization induced by a CO{sub 2} laser in H{sub 2} gas has been calculated. Laser light screening by a self-induced plasma density gradient is considered as the limiting factor for upscaling a CO{sub 2} laser-driven Inverse Cherenkov Laser Accelerator beyond 650 MeV/m. However, in near-resonance inverse Cherenkov acceleration where a shorter wavelength laser is used at a wavelength near the resonance of the gas (e.g. 248nm in H{sub 2}), t… more
Date: July 1, 1995
Creator: Liu, Y. & Pogorelsky, I. V.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Application of coherent lidar to ion measurements in plasma diagnostics

Description: A coherent lidar system has been constructed for the measurement of alpha particles in a burning plasma. The lidar system consists of a pulsed CO{sub 2} laser transmitter and a heterodyne receiver. The receiver local oscillator is a cw, sequence-band CO{sub 2} laser operating with a 63.23 GHz offset from the transmitter.
Date: March 1, 1997
Creator: Hutchinson, D. P.; Richards, R. K.; Bennett, C. A. & Simpson, M. L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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CO{sub 2} laser technology for advanced particle accelerators

Description: Short-pulse, high-power CO{sub 2} lasers open new prospects for development of ultra-high gradient laser-driven electron accelerators. The advantages of {lambda}=10 {mu}m CO{sub 2} laser radiation over the more widely exploited solid state lasers with {lambda}{approximately}1 {mu}m are based on a {lambda}{sup 2}-proportional ponderomotive potential, {lambda}-proportional phase slippage, and {lambda}-proportional scaling of the laser accelerator structures. We show how a picosecond terawatt CO{s… more
Date: June 1, 1996
Creator: Pogorelsky, I. V.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

An advanced open-path atmospheric monitor design

Description: The conceptual design of an open-path atmospheric monitor combines an acousto-optic tunable filter for emission spectroscopy (3-14 {mu}m) with a mid-IR (4.6-5.4 {mu}m) for absorption spectroscopy. It utilizes mostly commercially available components, covers a large area ({approximately}4 km radius), measures the distance to any reflecting object, can take measurements along any line-of-sight, and is eye safe. Of twenty test pollutants it is to detect, the concentrations of all twenty will be me… more
Date: May 1, 1996
Creator: Taylor, L.; Suhre, D. & Mech, S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Computational methods for describing the laser-induced mechanical response of tissue

Description: Detailed computational modeling of laser surgery requires treatment of the photoablation of human tissue by high intensity pulses of laser light and the subsequent thermomechanical response of the tissue. Three distinct physical regimes must be considered to accomplish this: (1) the immediate absorption of the laser pulse by the tissue and following tissue ablation, which is dependent upon tissue light absorption characteristics; (2) the near field thermal and mechanical response of the tissue … more
Date: February 1, 1994
Creator: Trucano, T.; McGlaun, J. M. & Farnsworth, A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Picosecond CO{sub 2} laser for relativistic particle acceleration

Description: A table-top 20-GW 50-ps CO{sub 2} laser system is under operation at the Brookhaven Accelerator Test Facility. We compare laser performance with model predictions. Extrapolations suggest the possibility of compact terawatt CO{sub 2} laser systems suitable as laser accelerator drivers and for other strong-field applications. Latest progress on an Inverse Cherenkov Laser Accelerator experiment is reported.
Date: June 1, 1994
Creator: Pogorelsky, I.; Ben-Zvi, Ilan; Kimura, W. D.; Kurnit, N. A. & Kannari, F.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Design Analysis for a 100-MeV Inverse Cerenkov Laser Accelerator

Description: The analysis of a 100-MeV demonstration experiment based upon inverse Cerenkov acceleration (ICA) is presented. This experiment would use the Accelerator Test Facility (ATF) at Brookhaven National Laboratory. With 50-GW of delivered laser peak power from the ATF CO{sub 2} laser, our analysis indicates the 65-MeV ATF e-beam can be accelerated to >165 MeV using three stages of acceleration in {approximately}1 m of total length. The number of electrons accelerated can be raised to {approximately}1… more
Date: December 31, 1993
Creator: Fontana, J. R.; Kimura, W. D.; Steinhauer, L. C. & Pogorelsky, I.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Scalable nanosecond CO/sub 2/ laser technology. Progress report for period November 7, 1976--January 7, 1977

Description: This second bi-monthly progress report on the Scalable Nanosecond CO/sub 2/ Laser Technology Program covers work performed from November 8, 1976 to January 7, 1977. Under Task I - Saturable Absorber Studies, small signal absorption measurements over the 9 and 10 ..mu.. bands were carried out on various molecules to determine their potential as gain isolators. Saturation and relaxation experiments are being set-up to further evaluate some of these absorber media. Continued modeling and theoretic… more
Date: February 1, 1977
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Electron acceleration in preformed plasma channels with terawatt CO{sub 2} laser

Description: Extended cylindrical plasma channels produced under gas breakdown by axicon-focused laser beams may be used as optical waveguides in laser-driven electron accelerators. Plasma channeling of the laser beams will help to maintain a high acceleration gradient over many Rayleigh lengths. In addition, the rarefied gas density channel produced after the optical gas breakdown, and followed by a plasma column expansion, reduces multiple scattering of the electron beam. A high-power picosecond C0{sub 2}… more
Date: February 1, 1995
Creator: Pogorelsky, I. V.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Waveguiding by Axicon-Focused Laser Beams

Description: We propose a method for formation of a long plasma waveguide based on axicon focusing of a radially polarized CO{sub 2} laser pulse into a uniform, low density discharge plasma. simulations demonstrate that an extended cylindrical plasma channel with a wall height {Delta}N{sub e} = 1.5 {times} 10{sup 16}cm{sup {minus}3} will be produced in a DC or RF discharge in 0.17 atm of hydrogen after axicon-focusing of a nanosecond 1-GW/cm{sup 2} CO{sub 2} laser pulse.
Date: June 12, 1994
Creator: Pogorelsky, I. V.; Kimura, W. D. & Liu, Y.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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ATF CO{sub 2} laser system upgrade to terawatt peak power

Description: This document describes the proposed upgrade of the 10-GW peak power 50-ps CO{sub 2} laser presently operational at the ATF to the 1 TW level at a shorter, 3--10 ps, pulse duration. The approach adopted is based on state of the art CO{sub 2} laser technology and an experience gained in the course of the ATF laser design and application for the laser accelerator experiment. The proposed upgrade is an economical way for the ATF to become in a short time among leading users facilities available fo… more
Date: May 1995
Creator: Pogorelsky, I. V.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

CO{sub 2} laser technology for advanced particle accelerators. Revision

Description: Short-pulse, high-power CO{sub 2} lasers open new prospects for development of ultra-high gradient laser-driven electron accelerators. The advantages of {lambda}=10 {mu}m CO{sub 2} laser radiation over the more widely exploited solid state lasers with {lambda}{approximately}1 {mu}m are based on a {lambda}{sup 2}-proportional ponderomotive potential, {lambda}-proportional phase slippage distance, and {lambda}-proportional scaling of the laser accelerator structures. We show how a picosecond tera… more
Date: June 1, 1996
Creator: Pogorelsky, I. V.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Application of interferometry and Faraday rotation techniques for density measurements on ITER

Description: There is a need for real time, reliable density measurement for density control, compatible with the restricted access and radiation environment on ITER. Line average density measurements using microwave or laser interferometry techniques have proven to be robust and reliable for density control on contemporary tokamaks. In ITER, the large path length, high density and density gradients, limit the wavelength of a probing beam to shorter then about 50 {micro}m due to refraction effects. In this … more
Date: December 31, 1995
Creator: Snider, R. T.; Carlstrom, T. N.; Ma, C. H. & Peebles, W. A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Experiments and Computational Modeling of Pulverized-Coal Ignition

Description: Under typical conditions of pulverized-coal combustion, which is characterized by fine particles heated at very high rates, there is currently a lack of certainty regarding the ignition mechanism of bituminous and lower rank coals. It is unclear whether ignition occurs first at the particle-oxygen interface (heterogeneous ignition) or if it occurs in the gas phase due to ignition of the devolatilization products (homogeneous ignition). There have been no previous studies aimed at determining th… more
Date: April 30, 1998
Creator: Chen, John C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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